A207903 Number of nX3 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 0 and 0 1 1 vertically

6, 36, 102, 261, 611, 1278, 2625, 5134, 9798, 18414, 33947, 62049, 112332, 201925, 361298, 643452, 1142526, 2023513, 3576387, 6311690, 11124765, 19589642, 34469830, 60616350, 106548039, 187215857, 328865096, 577561897, 1014154398

Offset

1,1

Comments

Column 3 of A207908

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 3*a(n-1) -4*a(n-3) -5*a(n-4) +9*a(n-5) +3*a(n-6) -2*a(n-7) -5*a(n-8) +2*a(n-9) -2*a(n-10) +a(n-11) +a(n-12) +a(n-13) -a(n-14)

Example

Some solutions for n=4
..0..0..1....0..1..1....1..0..0....0..1..1....0..0..1....0..1..1....1..0..0
..1..0..0....1..1..0....0..1..1....1..0..0....1..0..1....1..0..1....0..0..1
..0..1..1....0..0..1....1..0..0....0..0..1....0..1..1....0..1..1....1..1..0
..1..0..0....1..0..0....0..0..1....1..1..0....0..0..1....1..0..1....0..0..1

Crossrefs

Sequence in context: A207939 A207462 A086113 * A267714 A207747 A208023

Adjacent sequences: A207900 A207901 A207902 * A207904 A207905 A207906

Keyword

nonn

Author

R. H. Hardin Feb 21 2012

Status

approved